The ObjectManager.ObjectUpdate event occurs when the simulator sends an ObjectUpdatePacket containing a Primitive, Foliage or Attachment data
Note 1: The ObjectManager.ObjectUpdate event will not be raised when the object is an Avatar
Note 2: It is possible for the ObjectManager.ObjectUpdate to be raised twice for the same object if for example the primitive moved to a new simulator, then returned to the current simulator or if an Avatar crosses the border into a new simulator and returns to the current simulator